Case Study 1 - Cement plant

Waste Heat Recovery from hot gases exhausted by Preheater Cyclones and Clinker Cooler of Cement Plant

System Description

Initial situation

• The cement plant exhausts huge quantity of flue gas at high temperature from Pre heater and Clinker Cooler.
• The flue gas goes to stack through gas cleaning equipment such as ESP, Bag Filter etc.
• Before exhausting to atmosphere, the flue gas is cooled in equipments such as Gas Conditioning Tower, Forced Draft Cooler, Downcomer duct water spray etc.
• The heat in flue gas was being wasted into the atmosphere.

Challenges

• The flue gas are extremely dusty. The dust in Pre heater gas is fine, soft & sticky and has concentration of 70 to 80 gm / NM³ approx. The dust in Clinker Cooler gas is coarse , hard & abrasive and has concentration of 50 to 70 gm / NM³ approx.
• The pressure drop across the waste heat recovery system was required to be maintained within the allowable limits of the existing ID fan in Cement Plant.

System Schematic

Solution offered

• Patented design of Vertical Co-Flow boiler suitable to handle highly dust laden gases
• Waste Heat Recovery Boilers are installed on both Pre heater and Clinker Cooler exhaust gas.
• Heat is recovered from the flue gas in the form of superheated steam.
• The superheated steam drives Steam Turbine Generator to produce electric power.
• The exhaust steam is condensed in water cooled condenser.

Process Schematic

Results

Installation Photograph